by William M. Welch, USA TODAY

by William M. Welch, USA TODAY

JOHANNESBURG, South Africa - Presidents and grandchildren will join a massive throng of mourners Tuesday for a tribute to Nelson Mandela, the embodiment of this nation's struggle for democracy and champion of human rights.

On Monday, police and the government were bracing for the crush of mourners at the soccer stadium where the service would take place. South Africans would be met with high-level security measures to protect heads of state that included President Obama, India President Pranab Mukherjee and Cuban President Raul Castro.

The stadium seats nearly 100,000 people. Overflow crowds were expected to push that number far higher. Several "overflow" stadiums had been established.

South Africans expressed pride in the respect accorded Mandela, the former president who served 27 years in prison fighting a system of white rule that has since been abolished. He died Thursday at his home at age 95.

Mandela lived "so magnificent a life that it cannot be held in a grave," the Rev. Mzwandile Molo of the Bethesda Methodist Church told The Times, a local newspaper.

Obama was to be among the handful of 70 or so dignitaries asked to speak during the tribute. Some of Mandela's grandchildren were also to share their thoughts.

Aides said Obama would spend time with Mandela's family during his visit.

Traveling with the president and his family aboard Air Force One were former president George W. Bush and wife Laura and former secretary of State Hillary Rodham Clinton. Former presidents Bill Clinton and Jimmy Carter were arriving separately.

"What we can say is ... all the events and those who attend them are safe," said Collins Chabane, minister for Performance Monitoring and Evaluation.

Anticipating enormous crowds, the government said parents bringing children younger than 8 must write their mobile phone numbers in marker on the forearms of each child.

Military, police and intelligence services have all been activated for what may be the largest memorial service in decades. On local radio, broadcasters were warning of huge logistical hurdles and advising people to take public transportation as close parking would be banned.

Mandela's body will be taken in a procession to Pretoria, where he will lie in state from Wednesday through Friday. Johannesburg police said they expected tens of thousands of people waiting in long lines to get a last look at the man they call "Tata," which means "father."

Billboards put up by his political party, the African National Congress, could be seen throughout Johannesburg.

Mandela's remains would then be taken to a funeral and burial at his ancestral home in a rural part of the Eastern Cape province, far from Johannesburg.

The Mthatha airport in the Eastern Cape will only be used for the landing of heads of state, jamming up more distant airports where throngs of people and journalists were arriving, according to News24.

The Eastern Cape has a significant number of people of mixed race and Afrikaners, descendants of the Dutch colonialists who ruled this country until the early 1990s when Mandela became South Africa's first black president.